Throttle Quadrant Support Bracket Redo

Time: 4 Hours

Since my arm rests and throttle quadrant are all custom, meaning I deviated from what Van’s calls for, I had to do some engineering that’s unique for the support of the throttle quadrant cables. I took the idea from my buddy Glenn and made a bracket out of some large aluminum angle. I had completed this task and installed it some time ago and moved on to other tasks. Since then I was really happy with how the arms of the quadrant were moving and it felt like there was some binding. So yesterday I decided to investigate and see if I could fix the problem. What I found after a closer look was that I had actually measured the distance from the side skin to where the holes for the cables needed to be by about 3/8″. This meant that as the cables left the quadrant they angled outboard to hit the bracket holes. This caused each cable to cause a torquing action on the levers and caused the mixture and propeller cable ends to actually touch as they went through there motions in one spot. That was not good and needed to be fixed. So I decided to make a new bracket that would extend 3/8″ farther inboard. So I went about removing each cable from the quadrant then removed the two bolts holding the bracket. This allowed me to slide the bracket off of the three cables and remove it. I used it as a template and just extended the arm length by 3/8″. With the new measurements I went about drilling and trimming the angle to create a new bracket. I then did the task of getting the bend of the arm where the two bolts attach the bracket to the angle on the side skin. This was the time consuming part as it’s a little bit of a task to get the cables in and situated while checking the angle. Once that was done I bolted the bracket down and went through the process of setting the correct throw of the cable ends. These all looked good so I removed the bracket and primed/painted it so it would look presentable. Today the paint was dry so I reinstalled the bracket and worked the cables from outside to inside. First was the throttle cable as it’s the outermost cable on the quadrant. Once I had the throw all set and got the throttle arm on the servo to hit the full and idle stops I locked the cable arm in place with the nut and attached it to the throttle lever with the pin and cotter pin. I repeated this process for both the propellor and mixture cable. The propellor arm has given me the most problems part due to the angle that it goes through the bracket and the arm length on the propellor governor. What I ended up with was the prop lever goes to the full forward position on the quadrant and is short of the full aft portion by 3/8″ or so. I’m ok with this as it will never be in that full aft position and only off the full forward position a little as you increase the propellor pitch and reduce the engine RPM. The mixture arm works perfect allowing the full rich and idle cut-off.All three cables operate much smoother and there is no binding at all. I’m happy about that but I’m happy I spent four hours repeat a process but that part of experimental building. One other thing I did was to give the RV-8 some fresh air so I could sweep out the hangar. She really looks good stretching her legs after a long winter being cooped up!

Wings Back On

Time: 6 Hours

We have been busy getting all the things done in the new home to make it ours. Like ripping up old ceramic tile to make way for new hardwood. That was not a fun project but it’s all ripped up and ready for the installers. In-between that work I have been doing little projects in the hangar to get it organized. I also got my hands on the RV to start building again. One of the items I was unhappy with when I put the wings on the first time was the length of the wire bundles coming out of the wings. I found them to be a little short to work on with the tight space you end up with when the wings are on. So since I had the wings off again I decided to add 12″ to each of the bundles to give me plenty of length. I also figured that I would finish up the little bit of fiberglass tasks to the control surfaces, the rudder and elevators. I just needed to fill some pin holes and smooth the transitions out a little. A composite pro I am not and hope to get some help when it comes painting time to make these perfect. I used some filler primer to identify the holes and used Super-Fil to make the corrections. With the rudder pin holes taken care of and a coat of primer on I put the rudder on the vertical stabilizer and bolted it in place. I also put the AeroLED tail light in as well.I then spent two hours putting in the new close tolerance bolts in to secure the wings…again. The process was just the same as before, I froze the bolts and used LPS lubricant. The rivet gun at low pressure worked to drive them into position. The hardest part of the whole ordeal, as before, was to torque the bolts. I worked one bolt and then took a little break as leaning over the side wall of the fuselage even with padding was not very comfortable. So that’s a good start to being in my very own hangar that’s ten feet from my back door! I can not wait to be able to just walk out and go for a flight or a trip.

Wings On!

Time: 6 Hours

This morning I had breakfast with my buddy Glenn in preparation for helping me put my wings on. Now that the RV is at an airport I can put the wings on permanently so that I can continue to work on stuff while I wait to save up for my propellor. Since we have had my wings on and off two times before the process was pretty easy for us. We used the temporary bolts initially to hold the wings in place while I prepped for the final close tolerance NAS bolts. I had put all the bolts in the hangar freezer in hopes that they would shrink ever so slightly. I also picked up a can of LPS-2 lubricant that Vans recommends. Then I laid out several different tools, hammers and my rivet gun with the flush set in place. I started with the hard to get bottom bolts with the larger ones first. I pulled a bolt from the freezer and sprayed the shank with the LPS. Then I inserted it by hand as far as they would go followed by a few hits with a mallet. Then to drive them all the way I used my rivet gun and flush set with some duct tape on the face to drive the bolt thru. I just used a low PSI setting and it worked really well. I drove the two lower large bolts then the top followed by the two smaller bottom bolts then the top two. This process worked pretty slick and only took an hour.

Now the fun job of putting a washer and nut on all these bolts and torquing them. The large bolts get torqued to 520-630 in/lbs and the smaller ones to 80-100 in/lbs. not much to show on that process other than is was very time consuming and a pain to do. It didn’t help that it was 91° today and a little humid. After I finished I put some orange torque seal on to show that they were torqued.

There are also two AN-4 bolts that screw into nutplates from the aft side of the center section, I torqued those as well.

Fun day and felt good to sweat and swear a little while working on the RV! It’s been a while and I’m glad to be back at it. I have so many projects and tasks to do now that the wings are on and I’m excited to get at it!

Pilot Shoulder Strap Clip

Time: 2 Hours

One thing I have read about is the complaints of how the pilots shoulder straps don’t stay into position on the roll bar behind their seat. The straps are held on with a loop of the strap around the roll bar. Since the roll bar extends outward for a little bit and bends downward the straps have nothing to retain them and can slide outward. This means you have to fidget with them to get them into position. Big deal? No but since I have time on my hands I decided to come up with a solution. In the shop I have these wall units that have a bunch of little drawers in them. They are clear plastic and house all my rivets, screws and so on. I have had them since I started my build. Anyways these set of drawers came with these flat clips on the back that you could use to hang on the wall. These clips were meant to slid into a receptacle that would get screwed to the wall. I held on to these receptacles for some reason. While I was digging thru some parts I found them and a light bulb went off. They were the same width on the inside as the width of the shoulder straps. So I devised a plan to screw these to the underside of the roll bar to hold the straps in place. You may be having a hard time picturing these but in the following photos hopefully they make sense. First I did some test while sitting in the seat as to where I wanted these to align on the roll bar so they were comfortable. Then I marked the location and removed all the parts. I fine tuned the marks on tape that I put around the roll bar to protect the paint. To get the two holes aligned and marked for drilling I attached them to the roll bar with zip ties. In the photo you see the clip zip tied with two small washers taped to the clips. This was to make up the space of the clip so the zip tie didn’t squeeze the clip too much so I could get a good mark on the holes.

Now you have an idea what these clips looked like. On each end is a hole that’s countersunk for a flat head screw. This hole fits a #8 screw perfectly. So I marked the holes through the clips onto the tape after I had them aligned along the roll bar. I removed the zip ties and the clips and drilled and tapped for #8 screws while laying down inside the fuselage. I tell you having a bunch of Harbor Freight moving blankets is key to protect your back from all the protruding parts. With the holes drilled, tapped and cleaned up I put then shoulder straps in place and attached the clips with screws.

Another little project done and making progress. Simple yet effective solution to a problem.

More Fiberglass

Time: 4 Hours

I removed the peel ply from the canopy skirt to reveal nice layups over the horizontal rivet lines. So I repeated the process for the three vertical rows on each side. 

I then removed the ply peel from the gear leg fairings and sanded them down to prep for pin hole filling. 

After that I went on to the wheel pants. As I discussed in my last post I filled the uneven space between the bracket and the pant with epoxy/flox. That was pretty easy with the outboard bracket since it attaches close to the opening and I could get my hands in there. Now the inboard bracket is another story as there isn’t room for me to get my hands in there. I did a little research online and saw another builders idea and figured I would follow suit. The idea is to drill several extra holes around the screw holes in the pants. Then put the pants into position securing them with cleko’s on the put board and wood blocks at the aft end of the pants to keep the inboard holes aligned and not moving. Then with the same mixture of epoxy/flox use a syringe to inject the mixture in the holes and fill the void. 

This worked really well and I will repeat this process with the forward half of the pants. I finished up the day by putting a coat of UV smooth prime on the gear leg fairings. Tomorrow will be a sanding day.